Hydraulic driving means for operating hatch covers



H. J. SCHURINK HYDRAULIC DRIVING MEANS FOR OPERATING HATCH COVERS FiledJan. 23, 1964 Jan. 31, 1967 3 Sheets-Sheet 1 Jan. 31, 1967 H. J.scHURlNK HYDRAULIC DRIVING MEANS FOR OPERATING HATCH COVERS v Filed Jan.23, 1964 3 Sheets-Sheet 2 INVENTOR.

Jan- 31, 1957 H. J. scHuRlNK 3,301,313

HYDRAULIC DRIVING MEANS FOR OPERATING HATCH COVERS Filed Jan. 23, 1964-3 Sheets-Sheet 3 149 /4'3 Uff, 5.0

v7/ /uj 9 Lid@ BY i United States Patent Ofice 3 301.313 HYDRAULICDRlVlN MEANS FOR OPERATlNG HATCH CVERS Herbert Jan Schurink., Hilversum,Netherlands, assigner to Aktiebolaget Gtaverken, Goteborg, Sweden FiledJan. 23. 1964, Ser. No. 339.812 Claims priority, applicationNetherlands, Fel). 1, 1963, 288,484 1 Claim. (Cl. 160-188) The inevntionrelates to a hydraulic driving mechanism for operating a hatchway coveror the like, provided with a reversible hydraulic motor drivinglyconnected with the cover and included in a hydraulic system whichfurther comprises an oil tank and a hydraulic pump driven by aswitch-controlled electromotor, one of the sides of the pump beingconnected with one of the sides of the hydraulic motor through ahydraulic conduit.

In a known hydraulic driving mechanism of this type use is made of anon-reversible hydraulic pump driven by a non-reversible electrcmotor.Between the hydraulic pump and the hydraulic motor, a hydraulicswitching valve is arranged which valve may be controlled for connectingthe pressure oil supply conduit leading from the pump with one side orthe other of the hydraulic motor in order to operate the latter in onedirection or the other as desired for moving the hatchway cover towardsits closed or opened position.

It is an object of the invention to provide a hydraulic drivingmechanism which may be controlled in an easier manner.

It is a further object of the invention to simplify a hydraulic drivingmechanism incorporating a hydraulic motor of a type known under the nameHydrautorque hinge.

Another object of the invention is the provision of such hydraulicrdriving mechanism wherein no flexible oil hoses are needed between thehydraulic motor and the hydraulic pump.

To this end, the hydraulic driving mechanism according to the inventionis characterized in that the electromotor and the hydraulic pump arereversible, one of the sides of the pump being connected with one of thesides of the hydraulic motor by a hydraulic conduit and the other sideof the pump being connected with the other side of the hydraulic motorby a separate hydraulic con duit, the switch controlling theelectromotor being a reversing switch.

For operating the hydraulic driving mechanism according to theinvention, it sutiices to switch on the reversible electromotor in thedesired direction, which may be done in a simple manner with the aid ofan electrical reversing switch provided for controlling the supply ofelectric current to the electro'motor.

The invention will be further explained by reference to the drawings.

FIG. 1 schematically shows a preferred embodiment of the invention usinga Hydrautorque hinge;

FIG. 2 is a perspective view showing the use ofl the Hydrautorque hingeaccording to FIG. 1 in a hatchway cover comprising two movable sections;

FIG. 3 schematically shows another embodiment of the invention using adouble acting hydraulic cylinder.

The embodiment shown in FIG. l comprises a socalled Hydrautorque hinge1, which constitutes the driving connecting member of a pivotable hatchcover, and

mainly consists of a cylinder 2 in which two pistons 3 and 4 areslidably supported.

Each of the -pistons 3 and 4 is connected with a sleeve 5, or 6respectively, comprising an internal thread and external rectilinearsplines. The internal thread of each SJW-1,313 Pat-vented Jan. 31, 19,57

of the sleeves 5 and 6 engages a corresponding external thread 7, 8 ofan associated rotatable, non-slidably supported shaft 9, 10 of whicheither end is provided with rectilinear splines 11, 12. The externalrectilinear splines of each of the sleeves 5 and 6 engage correspondinginternal splines of an associated extension 15, 16 of the cylinder 2, sothat the sleeves 5 and 6 may slide with respect to the extension 15 and16, but cannot turn.

Furthermore, each of the extensions 15 and 16 is provided with externalrectilinear splines 17, 18. The cylinder 2 is provided with threeopenings 19, 20 and 21 each having a nipple for connection with an oilconduit; the opening 19 debouches in the middle of the cylinder 2,whilst the two remaining openings 2l) and 21 each debouch at one of theends of `this cylinder 2, in such manner that each piston 3, 4 is alwayslocated be tween the middle opening 19 and the associated outei` opening20 or 21.

By means of suitable fittings, the two sets of splines 11, 12 areattached to a cover section, and the other sets of splines 17, 18 areconnect-ed to another cover section or to a fixed part of the ship, sothat the first-mentioned cover section may swing around the other coversection or around said fixed part to open or to close the access to ahold. After admitting oil under pressure to the cylinder 2 through themiddle opening 19 between the pistons 3 and 4, the latter together withthe sleeves 5, 6 are pressed outwardly from the position as shown inFIG. 1, whereby'a rotation of the shaft 9, 10 and of the splines 11, 12formed thereon relative to the cylinder 2 and its extensions 15, 16 withthe splines 17, 18 is effected, so as to swing the first-mentioned coversection in a certain direction relative to said other section or saidfixed part.

lf oil under pressure is admitted to the cylinde-r 2 through theopenings 20 and 21, the pistons 3 and 4 together with the sleeves 5, 6are moved inwardly, whereby a relative rotation of the shaft 9, 10 inthe opposite direction is effected, so as to move the cover section inthe latter direction.

As shown in FIG. 2 the sets of rectilinear splines 11, 12 of theHydrautorque hinge are fixed t'o a cover section 67 by means of fittings66, `65, respectively, whereas the other sets of splines 17, 1S are xedto a cover section 70 by means of fittings 69, 68 respectively so thatthe cover sections 67 and 70 are connected with each other for pivotalmovement about the horizont-al axis of the cylinder 2 of theHydrautorque hinge 1.

The lcover section 70 is journalled with respect to the fixed shipsstructure 72 at its end 71 remote from the Hydrautorque hinge 1 forpivotal movement about an laxis parallel to the axis of the cylinder 2.The end 73 of the cover section 67v remote from the Hydrautorque hinge 1is provided with rollers 74 on -both sides to run over the fla-t upperface 75 of the hatchway coaming 76 surrounding the hatchway opening 77lto be closed by the cover sections 67 and 76.

In their opened position as shown in FIG. 2, the cover sections 67 and70 stand up side by side leaving the hatchway opening 77 unobstructed.In this position, the Hydrautorque hinge 1 is in the condition whereinthe pistons 3, 4 have been moved outwardly.' By supplying pressure oilto the cylinder 2 of the Hydrautorque hinge 1 through the openings 2()and 21 the Hydrautorque hinge 1 may be icaused t-o swing the coversections 67, 70 from the position shown in FIG. 2 into a closed position(not shown) wherein the cover sections 67, 70 lie up on the upper face75 of the hatchway coaming 76 aligned with each other to keep theyhatchway'opening 77 closed. In this position, the Hydrautorque hinge 1is in the condition shown in FIG. 1 wherein the pistons 3, 4 are ad- .3jacent each other. By supplying pressure oil to the cylinder 2 of theHydrautorque hinge 1 through the middle opening 19, the Hydraut-orquehinge 1 may be caused to swing the cover sections 67, 70 back again fromtheir closed position intoy their opened position as shown in FIG. 2.

It is pointed out that the amount of oil contained in the Hydrautorquehinge 1 is independent of the position of the pistons 3 and 4, so thatthe oil supply or discharge through the middle opening 19 is alwaysequal to the oil discharge or supply through the openings 20 and 21.

It ywill be understood that a considerable number oi Hydrautorque hinges1 is required on a ship to operate all cover sections.

As shown in FIG. 1, each of these Hydrautorque hinges 1 is included in aseparate hydraulic system, comprising a reversible electrornotor 22,coupled with a reversible hydraulic pump 23, symmetrically connectedthrough conduits 24, with a symmetrical pair of back pressure valves 26,27. The valves 25 and 27 are loaded by springs 28, 29 tending to pressthe valves on their seats in the partitions 3i), 31 so as to close thelbores 32, 33 in these partitions. A piston 34 is slidable in bothdirections within a Icylindrical ybore 35, which is connected to theconduits 24 and 25 on both sides of the piston 34. The ypiston 34 isprovided on each side with a pin 36, 37 extending through an associatedbore 32, 33.

By means of a suflicient pressure diierence between the conduits 24 and25, lthe piston 34 may be shifted in either direction, so that one ofthe pins 36, 37 engages the associated valve 216, 27 and lifts the samefrom its seat against the yaction of the spring 2S, 29, so that theybore 32, 33 in the partition 3), 31 remote from the conduit 24, 25 withthe higher pressure is opened.

The valve 26 is connected through a yconduit 3S with the middle opening19, while the valve 27 is connected through a conduit 39 wi-th the twoouter openings 20 and 21 of the Hydrautorque hinge 1.

The conduits 24 and 25, further, com-prise non-return suction valves 4t)and 41 connected with an oil tank 47.

The conduits 38, 39 are each connected through a conduit 42, 43 with anadjustable safety valve 45, 44, which is opened when a predeterminedpressure in the conduits 38, 39 is surpassed, so as t-o allow the oil toow back into the tank 47 through a common discharge conduit 45.

The rectangle 47, drawn in dot-and-dash lines, indicates the oil tank;all components surrounded by this rectangle may be combined with thetank to -a unit ,mounted on one of the cover sections.

ln FIG. 2 the reversible e ectromotor 22 and the hydriaulic tank 47within which the reversible hydraulic pump 23 has been enclosed, as wellas the hydraulic conduits 38, 39 (indicated in dot-and-dash lines) areall mounted on the cover section 76. It is to be noted that thehydraulic tank 47 needs only la very small oil capacity since the amountof oil contained by the Hydrautorque hinge 1 is constant as mentionedabove. An electric cable 78 extends between the reversible electromotor22 and an electrical reversing switch 79 mounted on the fixed shiplsstructure and provided with a handle 80 for controlling the supply ofelectrical current to the reversible electromotor 22 so -as to have theelectromotor 22 driving the hydraulic pump 23 in one direction or theother or to stop the motor 22 as desired.

Electrical current may be supplied to the reversing switch 79 by meansof an electrical cable 81 comprising a connector 82 to be plugged intothe housing of the switch 79.

When the Areversible pump 23 is driven in a certain direction, thepressure in conduit 24 is higher than in conduit 25, so that the piston34 is moved to the right from its central position and the valve 27 isopened against the action of the spring 29 to connect they conduit 39with the conduit 25 having the lower pressure. At the same time, thehigher pressure in conduit 24 opens the valve 26 against the action ofthe spring 28 in order to connect the conduit 38 with the conduit 24having the higher pressure. As a consequence, the pump 23 supplies oilto the Hydrautorque hinge 1 through the conduit 24, the valve 2'6, theconduit 38 and the middle opening 19, while an equal amount of oil isdischarged and returned to the pump through the outer openings 20, 21,the conduit 39, the valve 27 and the conduit 25; thus, the Hydrautorquehinge 1 is operated in one direction. If the electromotor 22 and thepump 23 are reversed, the conduit 2S will have a higher pressure thanthe conduit 24, so that the valve 27 is opened to connect the conduit 25with the conduit 39, and the piston 34 is moved to the left to open thevalve 26 in order to connect the conduit 24 with the conduit 38. As aconsequence, the pump 23 supplies oil to the outer openings 20, 21 ofthe Hydrautorque hinge 1 through the conduit 25, the valve 27, and theconduit 39, and an equal amount of oil is returned to the pump 23through the opening 19, the conduit 38, the valve 26 -and the conduit24, whereby the Hydrautorque hinge 1 is operated in the oppositedirection.

It is pointed out that the hydraulically operated back pressure valves26 and 27 allow the pump 23 to drive the Hydrautorque hinge 1 in eitherdirection, but prevent the pump 23 from being driven by the Hydrautorquehinge 1 under the inuence of the weight of one or more cover sections,although both the pump 23 and the Hydrautorque hinge 1 are reversible.Thus, it is impossible that an entirely or partially open hatch cover isclosed by its own weight. This applies to both driving directions oftheHydrautorque hinge 1.

1n the embodiment shown in FIG. 3, use is made of a double actinghydraulic cylinder 48, in which a piston 49 is slidably supported; thepiston 49 is attached to the end of a piston rod 50 projecting out ofthe cylinder 48.

Openings 51 and 52 are formed at the two ends of the cylinder 48, sothat the piston 49 is always loc-ated between these openings. Eachopening 51, 52 is provided with a nipple for the connection of a conduit24 and 25,

respectively. Each of the conduits 25, 24 leads to a side of thereversible hydraulic pump 23 respectively, which pump 23 is driven bythe reversible electromotor 22.

The cylinder 4S is mounted between a cover section and a xed part of theship (not shown).

By admitting oil under pressure to the cylinder 48 through the opening51, the piston 49 and its rod 50 may be moved to the right from theposition as shown in FIG. 3 for driving the cover section; by admittingoil to the cylinder 48 through the opening 52, the piston 49` and therod 5t) may lbe moved in the opposite direction to return the coversection to its initial position.

It is pointed out that the amount of oil contained in the hydrauliccylinder 48 is dependent on the position of the piston 49, so that theoil supply or discharge through the left-hand opening 51 is alwayslarger than the oil discharge or supply through the right hand opening52. The difference is equal to the amount of oil displaced by the pistonrod 50.

A hydraulic operated valve member is provided, consisting of a casing 53with a bore 54, in which two plungers 56, 57, interconnected by anintermediate rod 55, are slidably supported. The plungers 56 and 57 maybe moved in downward direction from the position shown in FIG. 3 againstthe action of a spring 58, interposed between the plunger 57 and theyend wall 6) of the casing 53, which end wall 60 is provided with a bore59; this movement of the plungers 56, 57 may be brought about by the oilpressure in the conduit 25, which is connected for this purpose througha conduit 61 with the bore 54 above the plunger 55, provided that thepump 23 rotates in the appropriate direction. The plunger 57 thenreleases an annular groove 62, connected with a conduit 63 leading tothe oil tank 47, so that the conduit 63 is brought into communicationwith the part of the bore 54 between the plungers 56 and 57. This partof the -bore 54 is connected to the conduit 24 through a conduit 64,

so that the oil to the left of the piston 49 may escape through theconduit 24, the conduit 64, the space of the bore 54 between theplungers 56 and 57, the annular groove 62 and the conduit 63 to the tank47, in order that the piston 49 and the rod 50 may move to the left.When the pump 23 is stopped, so that the pressure in the conduit 25disappears, the plungers 56 and 57 are returned to their initialposition by the spring 5S, so that the annular groove 62 is shut off bythe plunger 57, and the oil can no longer escape through conduit 24 tothe tank 47. In this case, the piston 49 and the rod 50 are blockedagainst any movement to the left, because there is no possibility todischarge the oil which the rod 50 tends to displace on its inwardmovement, as the nonreturn suction valves 40, 41 prevent this oil frombeing discharged to the tank 47.

I the pump 23 is driven in the opposite direction, so that the conduit24 is brought under pressure, the piston 49 and the rod 50 are moved tothe right. The valve member 53, 56, 57, 62 remains inoperative in thiscase, in the position as shown in FIG. 3.

The difference between the amount of oil supplied to the cylinder 4S bythe pump 23 through the conduit 24 and the opening 51, and the smalleramount of oil returned from the cylinder 48 to the pump 23 through theopening 52 and the conduit 25, is taken from the tank 47 through thenon-return suction valve 41.

The conduits 24 and 2S are connected with adjustable safety valves 45and 44, provided with a common return conduit 46 to the tank 47.

In the embodiment as shown in FIG. 3, the cylinder 48 has to be arrangedin such manner that the piston rod 50 in its inward position is notsubjected by the cov-er section to an outwardly directed force.

When a plurality of hatch covers are each provided with one or morehydraulic motors 1 or 48, an extensive hydraulic conduit systemthroughout the ship is avoided, since each hydraulic motor 1 or 48 isinserted in a separate hydraulic system, of which the oil tank 47, theelectromotor 22, the hydraulic pump 23 and the hydraulically operatedvalve member 26, 27 or 57, 62 are arranged in the vicinity of theassociated hydraulic motor 1 or 48, as shown in the drawings.

I claim:

An hydraulic operating mechanism for a hatchway cover or the like havingiirst and second cooperating sections movable in relation to a fixedstructure, comprising, in combination,

a double-acting hydraulic motor fixed to said iirst cover section and tosaid second cover section in such a manner that it constitutes a hingebetwen said two cover sections;

a generally cylindrical tank for a supply of hydraulic liquid, -saidtank having substantially the same diameter as, and being arrangedcoaxially with, said hydraulic motor;

a reversible hydraulic pump enclosed within said tank;

a reversible electric motor driving said pump;

a cable supplying current to the electric motor;

a switch in the cable to reverse the direction of current to theelectric motor;

a rst hydraulic connection between one side of said pump and one side ofsaid hydraulic motor and a second hydraulic connection between the otherside of said pump and the other side of said hydraulic motor toconstitute a self-contained hydraulic circuit in which either of sai-dhydraulic connections may convey fluid to the motor while the -otherconnection returns fluid therefrom;

a spring-loaded non-return valve in each of said rst and secondhydraulic connections adapted to be opened under the influence ofhydraulic liquid pressure;

a Icommon valve housing for said valves;

a bore in said housing;

piston slidably disposed in said bore between the valves;

each of said rst and said second hydraulic connections from the pumpbeing connected to the housing between the pertaining Valve and thepiston in such a manner that hydraulic pressure produced by the pump ineither of said hydraulic connections causes the pertaining non-returnvalve to open and shifts the piston in the bore so yas to open also thenon-return valve in the other hydraulic connection which acts as returndow connection, said hydraulic operating mechanism being such that alloperating parts are readily accessible when the hatch covers are openbut are well protected when the hatch covers are closed.

References Cited by the Examiner UNITED STATES PATENTS ll/l956 3/19423/1956 10/1962 10/1964 l/1965 3/1965 HARRTSON R. MOSELEY, PrimaryExaminer.

I. K. BELL, Assistant Examiner,

